Synthetic cannabinoids (SCs) represent a major problem to society and their use is increasing. Synthetic cannabinoids have been marketed under the guise of “herbal incense,” and promoted by drug traffickers as legal alternatives to marijuana. Newer generations of synthetic cannabinoid substances are continually emerging in the U.S. illicit drug market.
N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-pentyl-1H-indazole-3-carboxamide, also known as AB-PINACA, is one such new-generation synthetic cannabinoid receptor agonist (SCRA). It has a core indazole structure and a carboxamide linkage. AB-PINACA was first identified as a component of synthetic cannabis products in Japan in 2012. It is similar in structure to the other new generation synthetic cannabinoids ADB-FUBINACA (N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide) and AB-FUBINACA (N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide). According to Drugs Forum website dosage is in the region of 2-15 mg.
The most common route of administration is via smoking, but the drug can also be taken orally and by inhalation. AB-PINACA is most frequently found as a component of herbal mixtures/blends suitable for smoking. AB-PINACA is described by users on the Drugs Forum website as ‘a stronger version of JWH-018’ and ‘twice as strong as the last batch of synthetic cannabinoids’. It is said to produce a ‘dreamy high’ and is said to be ‘very sedating . . . opium-like’. 5-Fluoro-AB-PINACA is considered ‘super-stimulatory’ and ‘way more potent than normal AB-PINACA’.
In 2013 AB-PINACA (and ADB-FUBINACA) was classed as a “Designated Substance” under the Pharmaceutical Affairs Law in Japan. AB-PINACA is a Schedule I drug in the USA. AB-PINACA has been scheduled in Victoria, Australia (2013). Structurally related AB-FUBINACA was temporarily made a Schedule I drug in the US in January 2014 due to imminent threat to public health.
The defining feature of the Pinaca family (See FIG. 1 for members and metabolites) is a 3-amido-indazole structure with a 1-N substituent and a N-amide substituent consisting of either 1-amino-1-carbonyl-3-methylbut-2-yl (Z═H) or 1-amino-1-carbonyl-3,3-dimethylbut-2-yl (Z═CH3) i.e.:
in which Z is H or CH3 and substituent may be selected from, but is not limited to, pentanoic acid, 5-fluoropentyl, 5-hydroxylpentyl, 4-hydroxylpentyl, pentyl, 5-fluoro-4-hydroxylpentyl; and (4-fluoro-phenyl)methyl.
Substituents off an indazole are numbered as follows:

Detection of this family and their key metabolites is necessary for toxicological screening and drug identification. Mass-spectrometry (MS) detection of Pinaca family members has been described (Takayama 2014). MS detection, however, is time consuming and requires expensive equipment as well as highly trained operators. A need exists for rapid detection of SC's Pinaca family.